Are long flights hazardous to your health?

Long plane trips can be uncomfortable, but a new study published in the journal Arteriosclerosis, Thrombosis and Vascular Biology suggests they can also pose hazards to your health, especially when it comes to a condition called deep vein thrombosis (DVT).

“Deep vein thrombosis is a clot that forms in a vein, usually one of the larger veins deep in the leg,” says Charles (Charlie) Brown III, M.D., an interventional cardiologist at Piedmont Heart Institute. “The danger with those is a mechanical problem. If you have a vein that’s an inch to an inch and a half in diameter, and it forms a big, hard clot that breaks off and goes into the channel of the heart, it actually obstructs the flow of blood through the heart to the point where you can’t pump any more blood through the left ventricle.” He says at this point, the clot can lead to death.

In the study, researchers found that tall, obese men are more than five times more likely than short, normal weight men to develop venous thromboembolism (VTE), a potentially lethal condition marked by deep vein blood clots (usually in the legs) and blood clotting in the lungs (pulmonary embolism).
Those men who are tall, but not obese, also have an increased risk. “If you are taller and have a longer vein, there is a longer segment that has a tendency to form a clot,” explains Dr. Brown.

Dr. Brown notes that there are several other groups of people who are at risk of developing DVT, such as those who are confined to a hospital bed for weeks at a time and people who have had hip or bone fractures and are confined to a cast. Additionally, “there are metabolic things that increase risk, such as taking certain medications or contraceptives.”

What should any of us do if we are on a long trip, regardless of our size, to prevent DVT?
“The difference between arteries and veins is that the venous flow is very dependent on muscular activity,” he says. He recommends anything that facilitates movement in your legs – like wiggling your toes and flexing your calf and thigh muscles – if you must sit for long periods of time.

So remember, if you are ever on a long flight or must sit for hours at a time, be sure to follow Dr. Brown’s tips to prevent blood clots. They could help save your life.

Additional Facts About the Study:

The study tracked the height and weight of more than 26,000 adults in Tromsø, Norway.

The study found that for women, being tall creates no additional risk, likely because women do not grow sufficiently tall, say researchers.

Obesity has long been known to be a risk factor for VTE, as have pregnancy, recent surgery, cigarette smoking, using oral contraceptives, having a family history of the condition and sitting for an extended period of time.

In the U.S., more than 275,000 people each year are hospitalized with deep vein clots or pulmonary embolism. Symptoms of this disorder include leg pain, tenderness or swelling.